132 



ORDER HEMIPTERA 



An interesting subdivision of the group includes the 

 Ortheziince which secrete a white calcareous secretion which 

 appears in plates or filaments extending from the body, often 

 as long parallel bars extending back some distance from the 

 body. A rather common species in the Northern States is 

 solidaginis , occurring on goldenrod. There also is included 

 in this group the very destructive cottony cushion scale, 

 Icerya purchasi, which for a time threatened the fruit 



Fig. 87. ^Pulvinaria innumerabilis: adult females in position on twigs 

 with egg sacs — natural size. (Howard, Div. Ent., U. S. Dept. Ag.) 



industry of California but which was brought under control 

 by the importation of the Australian lady bird {VedaVia 

 cardinalis). 



The subfamily Coccincp includes what are termed the soft 

 scales. The bodies of these are covered more or less com- 

 pletely with a waxy secretion which adheres firmly to the 

 body wall and furnishes a thick, more or less rigid protec- 

 tion to the body. Most of them adhere fixedly to the bark 

 or leaves but in some cases a migration at the time of moult- 



